Tissue fastening systems and methods utilizing magnetic guidance

ABSTRACT

Catheter based systems and methods for securing tissue including the annulus of a mitral valve. The systems and methods employ catheter based techniques and devices to plicate tissue and perform an annuloplasty.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of U.S. Non-Provisionalapplication Ser. No. 10/948,923, filed Sep. 24, 2004, which claims thepriority of U.S. Provisional Application No. 60/531,855 filed on Dec.23, 2003 (expired) and U.S. Provisional Application No. 60/554,314 filedMar. 18, 2004 (expired), the disclosures of which are herebyincorporated herein by reference.

U.S. Non-Provisional application Ser. No. 10/948,923 is also aContinuation-In-Part of U.S. Ser. No. 10/689,872, filed Oct. 21, 2003(issued), now U.S. Pat. No. 8,460,371, issued Jun. 11, 2013, whichclaims the priority of U.S. Provisional Application Ser. No. 60/420,095,filed Oct. 21, 2002. The disclosures of these applications are herebyfully incorporated by reference herein.

FIELD OF THE INVENTION

The present invention relates generally to techniques for treatingmitral valve insufficiencies such as mitral valve leakage due toprolapse, papillary muscle dysfunction, or annular dilation. Moreparticularly, the present invention relates to systems and methods fortreating a leaking mitral valve in a minimally invasive manner. Variousaspects of the invention further pertain more generally to magneticguidance and/or fastener delivery systems used for approximating orotherwise operating on tissue.

BACKGROUND OF THE INVENTION

Congestive heart failure (CHF), which is often associated with anenlargement of the heart, is a leading cause of death. As a result, themarket for the treatment of CHF is becoming increasingly prevalent. Forinstance, the treatment of CHF is a leading expenditure of Medicare andMedicaid dollars in the United States. Typically, the treatment of CHFenables many who suffer from CHF to enjoy an improved quality of life.

Referring initially to FIG. 1A, the anatomy of a heart 10, specificallythe left side of the heart 10, includes a left atrium (LA) 12 and a leftventricle (LV) 14. An aorta 16 receives blood from left ventricle 14through an aortic valve 18, which serves to prevent regurgitation ofblood back into left ventricle 14. A mitral valve 20 is positionedbetween left atrium 12 and left ventricle 14, and allows one-way flow ofblood from the left atrium 12 to the left ventricle 14.

Mitral valve 20, which will be described below in more detail, includesan anterior leaflet 22 and a posterior leaflet 24 that are coupled tocordae tendonae 26 which serve as “tension members” that prevent theleaflets 22, 24 of mitral valve 20 from going past their closing pointand prolapsing back into the left atrium. When left ventricle 14contracts during systole, cordae tendonae 26 limit the upward (towardthe left atrium) motion of the anterior and posterior leaflets past thepoint at which the anterior and posterior leaflets 22, 24 meet and sealto prevent backflow from the left ventricle to the left atrium (“mitralregurgitation” or “mitral insufficiency”). Cordae tendonae 26 arise froma columnae carnae or, more specifically, a musculi papillares (papillarymuscles) 28 of the columnae carnae. In various figures herein, someanatomical features have been deleted solely for clarity.

FIG. 1B is a cut-away top-view representation of mitral valve 20 andaortic valve 18. Anterior leaflet 22 and posterior leaflet 24 of themitral valve 20 are generally thin, flexible membranes. When mitralvalve 20 is closed (as shown in FIG. 1B), anterior leaflet 22 andposterior leaflet 24 are generally aligned and contact one another alonga “line of coaptation” several millimeters back from their free edges,to create a seal that prevents mitral regurgitation. Alternatively, whenmitral valve 20 is opened, blood flows downwardly through an openingcreated between anterior leaflet 22 and posterior leaflet 24 into leftventricle 14.

Many problems relating to mitral valve 20 may occur and may cause manytypes of ailments. Such problems include, but are not limited to, mitralregurgitation. Mitral regurgitation, or leakage, is the backflow ofblood from left ventricle 14 into the left atrium 12 due to an imperfectclosure or prolapse of mitral valve 20. That is, leakage often occurswhen the anterior and posterior leaflets to not seal against each other,resulting in a gap 32 between anterior leaflet 22 and posterior leaflet24.

In general, a relatively significant gap 32 may exist between anteriorleaflet 22 and posterior leaflet 24 (as shown in FIG. 1C) for a varietyof different reasons. For example, a gap 32 may exist due to congenitalmalformations, because of ischemic disease, or because the heart 10 hasbeen damaged by a previous heart attack. A gap 32 may also be createdwhen congestive heart failure, e.g., cardiomyopathy, or some other typeof distress which causes a heart to be enlarged. Enlargement of theheart can result in dilation (stretching) of the mitral annulus. Thisenlargement is usually limited to the posterior valve annulus and isassociated with the posterior leaflet, because the anterior annulus is arelataively rigid fibrous structure. When the posterior annulusenlarges, it causes the posterior leaflet to move away from the anteriorleaflet, causing a gap because the two leaflets no longer form propercoaptation, and this results in leakage of blood through the valve, orregurgitation.

Leakage through mitral valve 20 generally causes a heart 10 to operateless efficiently, as the heart 10 must pump blood both out to the bodyvia the aorta, and also back (in the form of mitral regurgitation) backinto the left atrium. Leakage through mitral valve 20, or general mitralinsufficiency, is thus often considered to be a precursor to CHF or acause of progressive worsening of heart failure. There are generallydifferent levels of symptoms associated with heart failure. Such levelsare classified by the New York Heart Association (NYHA) functionalclassification system. The levels range from a Class 1 level which isassociated with an asymptomatic patient who has substantially nophysical limitations to a Class 4 level which is associated with apatient who is unable to carry out any physical activity withoutdiscomfort, and has symptoms of cardiac insufficiency even at rest. Ingeneral, correcting or reducing the degree of mitral valve leakage maybe successful in allowing the NYHA classification grade of a patient tobe reduced. For instance, a patient with a Class 4 classification mayhave his classification reduced to Class 3 or Class 2 and, hence, berelatively comfortable at rest or even on mild physical exertion. Byeliminating the flow of blood backwards into the left atrium, therapiesthat reduce mitral insufficiency reduce the work load of the heart andmay prevent or slow the worsening of heart function and congestive heartfailure symptoms that is common when a significant degree of mitralinsufficiency remains uncorrected.

Treatments used to correct for mitral valve leakage or, more generally,CHF, are typically highly invasive, open-heart surgical procedures asdescribed below. In extreme cases, this may include implantation of aventricular assist device such as an artificial heart in a patient whoseown heart is failing. The implantation of a ventricular assist device isoften expensive, and a patient with a ventricular assist device must beplaced on extended anti-coagulant therapy. As will be appreciated bythose skilled in the art, anti-coagulant therapy reduces the risk ofblood clots being formed, as for example, within the ventricular assistdevice. While reducing the risks of blood clots associated with theventricular assist device is desirable, anti-coagulant therapies mayincrease the risk of uncontrollable bleeding in a patient, e.g., as aresult of a fall, which is not desirable.

Rather than implanting a ventricular assist device, bi-ventricularpacing devices similar to pace makers may be implanted in some cases,e.g., cases in which a heart beats inefficiently in a particularasynchronous manner. While the implantation of a bi-ventricular pacingdevice may be effective, not all heart patients are suitable forreceiving a bi-ventricular pacing device. Further, the implantation of abi-ventricular pacing device is expensive, and is generally noteffective in significantly reducing or eliminating the degree of mitralregurgitation.

Open-heart surgical procedures which are intended to correct for mitralvalve leakage, specifically, can involve the implantation of areplacement valve. Valves from animals, e.g., pigs, may be used toreplace a mitral valve 20 in a human. While the use of a pig valve mayrelatively successfully replace a mitral valve, such valves generallywear out, thereby requiring additional open surgery at a later date.Mechanical valves, which are less likely to wear out, may also be usedto replace a leaking mitral valve. However, when a mechanical valve isimplanted, there is an increased risk of thromboembolism, and a patientis generally required to undergo extended anti-coagulant therapies.

A less invasive surgical procedure involves heart bypass surgeryassociated with a port access procedure. For a port access procedure,the heart may be accessed by cutting between ribs or sometimes removingparts of one or more ribs, as opposed to dividing the sternum to openthe entire chest of a patient. In other words, the opening occursbetween the ribs in a port access procedure, rather than opening apatient's sternum.

One open-heart surgical procedure that is particularly successful incorrecting for mitral valve leakage and, in addition, mitralregurgitation, is an annuloplasty procedure. During an annuloplastyprocedure, a medical device—an annuloplasty ring—may be implantedsurgically on the left atrial side of mitral annulus (the attachment ofthe base of the mitral valve to the heart) to cause the size of adilated mitral valve annulus to be reduced to a relatively normal size,and specifically to move the posterior leaflet closer to the anteriorleaflet to aid anterior-posterior leaflet coaptation and thus improvethe quality of mitral valve closure and significantly reduce the amountof mitral insufficiency. FIG. ID is a schematic representation of anannuloplasty ring 34. An annuloplasty ring 34 is shaped approximatelylike the contour of a normal mitral valve 20. That is, annuloplasty ring34 is shaped substantially like the letter “D.” Typically, annuloplastyring 34 may be formed from a rod or tube of biocompatible material,e.g., plastic, that has a DACRON mesh covering.

In order for annuloplasty ring 34 to be implanted, a surgeon surgicallyattaches annuloplasty ring 34 to the mitral valve on the atrial side ofthe mitral valve 20. Conventional methods for installing ring 34 requireopen-heart surgery which involve opening a patient's sternum and placingthe patient on a heart bypass machine. As shown in FIG. 1E, annuloplastyring 34 is sewn to a posterior leaflet 24 and an anterior leaflet 22 ofa top portion of mitral valve 20. In sewing annuloplasty ring 34 ontomitral valve 20, a surgeon generally sews the straight side of the “D”to the fibrous tissue located at the junction between the posterior wallof the aorta and the base of the anterior mitral valve leaflet. As thecurved part of the ring is sewn to the posterior aspect of the annulus,the surgeon alternately acquires a relatively larger amount of tissuefrom the mitral annulus, e.g., a one-eighth inch bite of tissue, using aneedle and thread, compared to a relatively smaller bite taken of thefabric covering of annuloplasty ring 34. Once a thread has looselycoupled annuloplasty ring 34 to mitral valve tissue, annuloplasty ring34 is slid into contact with the mitral annulus 40 such that the tissueof the posterior mitral annulus that was previously stretched out, e.g.,due to an enlarged heart, is effectively reduced in circumference andpulled forwards towards the anterior mitral leaflet by the tensionapplied by annuloplasty ring 34 by the thread that binds theannuloplasty ring 34 to the mitral annulus tissue. As a result, a gap,such as gap 32 of FIG. 1C, between anterior leaflet 22 and posteriorleaflet 24 during ventricular contraction (systole) may be reduced andeven substantially closed off in many cases thereby significantlyreducing or even eliminating mitral insufficiency. After the mitralvalve 20 is shaped by ring 34, the anterior and posterior leaflets 22,24 will reform typically by pulling the posterior leaflet forward toproperly meet the anterior leaflet and create a new contact line thatwill enable mitral valve 20 to appear and to function properly.

Once implanted, tissue generally grows over annuloplasty ring 34, and aline of contact between annuloplasty ring 34 and mitral valve 20 willessentially enable mitral valve 20 to appear and function normally.Although a patient who receives annuloplasty ring 34 may be subjected toanti-coagulant therapies, the therapies are not extensive, as a patientis only subjected to the therapies for a matter of weeks, e.g., untiltissue grows over annuloplasty ring 34.

A second surgical procedure which is generally effective in reducingmitral valve leakage associated with prolapse of the valve leafletsinvolves placing a single edge-to-edge suture in the mitral valve 20that apposes the mid-portions of anterior and posterior leaflets. Withreference to FIG. 1F, such a surgical procedure, e.g., an Alfieri stitchprocedure or a bow-tie repair procedure, will be described. Anedge-to-edge stitch 36 is used to stitch together an area atapproximately the center of the gap 32 defined between an anteriorleaflet 22 and a posterior leaflet 24 of a mitral valve 20. Once stitch36 is in place, stitch 36 is pulled in to form a suture which holdsanterior leaflet 22 against posterior leaflet 24, as shown. By reducingthe size of gap 32, the amount of leakage through mitral valve 20 may besubstantially reduced.

Although the placement of edge-to-edge stitch 36 is generally successfulin reducing the amount of mitral valve leakage through gap 32,edge-to-edge stitch 36 is conventionally made through open-heartsurgery. In addition, the use of edge-to-edge stitch 36 is generally notsuitable for a patient with an enlarged, dilated heart, as bloodpressure causes the heart to dilate outward, and may put a relativelylarge amount of stress on edge-to-edge stitch 36. For instance, bloodpressure of approximately 120/80 or higher is typically sufficient tocause the heart 10 to dilate outward to the extent that edge-to-edgestitch 36 may become undone, or tear mitral valve tissue.

Another surgical procedure which reduces mitral valve leakage involvesplacing sutures along a mitral valve annulus around the posteriorleaflet. A surgical procedure which places sutures along a mitral valve20 will be described with respect to FIG. 1G. Sutures 38 are formedalong the annulus 40 of a mitral valve 20 that surrounds the posteriorleaflet 24 of mitral valve 20. These sutures may be formed as a doubletrack, e.g., in two “rows” from a single strand of suture material 42.Sutures 38 are tied off at approximately a central point (P2) ofposterior leaflet 24. Pledgets 44 are often positioned under selectedsutures, e.g., at the two ends of the sutured length of annulus or atthe central point P2, to prevent sutures 38 from tearing through annulus40. When sutures 38 are tightened and tied off, the circumference of theannulus 40 may effectively be reduced to a desired size such that thesize of a gap 32 between posterior leaflet 24 and an anterior leaflet 22may be reduced.

The placement of sutures 38 along annulus 40, in addition to thetightening of sutures 38, is generally successful in reducing mitralvalve leakage. However, the placement of sutures 38 is conventionallyaccomplished through open-heart surgical procedures. That is, like otherconventional procedures, a suture-based annuloplasty procedure isinvasive.

While invasive surgical procedures have proven to be effective in thetreatment of mitral valve leakage, invasive surgical procedures oftenhave significant drawbacks. Any time a patient undergoes open-heartsurgery, there is a risk of infection. Opening the sternum and using acardiopulmonary bypass machine has also been shown to result in asignificant incidence of both short and long term neurological deficits.Further, given the complexity of open-heart surgery, and the significantassociated recovery time, people who are not greatly inconvenienced byCHF symptoms, e.g., people at a Class 1 classification, may choose notto have corrective surgery. In addition, people who most need open heartsurgery, e.g., people at a Class 4 classification, may either be toofrail or too weak to undergo the surgery. Hence, many people who maybenefit from a surgically repaired mitral valve may not undergo surgery.FIG. 1H illustrates the cardiac anatomy, highlighting the relativeposition of the coronary sinus (CS) 46 running behind the posteriorleaflet 24 of the mitral valve 20. FIG. 1I is an illustration of thesame anatomy but schematically shows a cinching device 48 which isplaced within the CS 46 using a catheter system 50, with distal, mid,and proximal anchors 52 a, 52 b, 52 c within the lumen of the CS 46 toallow plication of the annulus 40 via the CS 46. In practice, theseanchors 52 a-c are cinched together, i.e., the distance between them isshortened by pulling a flexible tensile member 54 such as a cable orsuture with the intent being to shorten the valve annulus 40 and pullthe posterior leaflet 24 closer to the anterior leaflet 22 in a mannersimilar to an annuloplasty procedure. Unfortunately, since the tissuewhich forms the CS 46 is relatively delicate, the anchors 52 a-c areprone to tear the tissue during the cinching procedure, and the effecton the mitral annulus may be reduced by the position of the coronarysinus up more towards the left atrium rather than directly over themitral annulus itself. Other minimally invasive techniques have beenproposed and/or developed but have various drawbacks related to suchfactors as effectiveness and/or cases and accuracy of catheter-basedimplementation.

Therefore, there remains a need for improved minimally invasivetreatments for mitral valve leakage. Specifically, what is desired is amethod for decreasing the circumference of the posterior mitral annulus,moving the posterior leaflet forwards towards the anterior leaflet andthereby reducing leakage between an anterior leaflet and a posteriorleaflet of a mitral valve, in a manner that does not requireconventional surgical intervention.

SUMMARY OF THE INVENTION

The invention provides a method of modifying an annulus of a heart valvein a first general aspect. The annulus lies generally below the coronarysinus at least at one location. The method comprises fastening thecoronary sinus to the annulus to bring the annulus closer to thecoronary sinus at least at the one location, and then reducingregurgitation by modifying the annulus. For example, the annulus may bemodified by shortening the circumferential length (i.e., the arc length)of the annulus or changing the shape or other physical characteristic ofthe annulus. Fastening the coronary sinus can further comprise insertinga first guide element into the coronary sinus, directing a second guideelement into the left ventricle so it lies under and/or adjacent to theannulus, securing the first and second guide elements together, andapplying a fastener between the annulus and the coronary sinus.

The guide elements may be removed after applying the fastener, andtherefore act as a temporary anchor for the fastener delivery deviceand/or the tissue to be secured. Alternatively, the guide elements, orportions thereof, may be left in place. The guide elements may comprisemechanical fasteners or other types of fasteners such as magnets (i.e.,magnetic elements), or combinations thereof. One guide element of theinvention comprises first and second spaced apart magnets on the distalsupport portion of a catheter. Repelling poles of the magnets face eachother to create a circumferential virtual pole emanating around the gapformed between the spaced apart magnets. Securing the first and secondguide elements together can further comprise magnetically attracting thefirst and second guide elements together. The same catheter device maybe used to direct the second guide element and apply the fastener. Inaddition, the method can include applying a second fastener to theannulus, coupling the first and second fasteners together, and reducingthe distance between the first and second fasteners to reduce thecircumference of the annulus. In this case applying the first and secondfasteners can occur through the same catheter device. More particularly,the method can involve serially applying the first and second fastenersthrough one lumen in a catheter device or, as another example, applyingthe first and second fasteners through different lumens of the samecatheter device. In another aspect of the invention, at least oneflexible tensile member is used to couple the first and second fastenerstogether and the flexible tensile member is tensioned to reduce thedistance between the first and second fasteners. Shortening thecircumferential length of the annulus can further comprise fastening aflexible fabric to the annulus and shortening the circumferential lengthof the flexible fabric.

In another general aspect, a method of modifying an annulus of a heartvalve comprises applying first and second fasteners on opposite sides ofthe annulus through at least one catheter thereby holding heart tissuebetween the first and second fasteners, applying third and fourthfasteners on opposite sides of the annulus through at least one catheterthereby holding heart tissue between the third and fourth fasteners. Aswith the fasteners applied in the various aspects of this invention,different chateters or different catheter portions may be used to applythe different fasteners or the same catheter may be used. The first andsecond fasteners are coupled and the third and fourth fasteners arecoupled using at least one flexible tensile member. The distance betweenadjacent ones of at least two of the first, second, third and fourthfasteners is reduced by applying tension to the flexible tensile memberthereby modifying the annulus.

The first, second, third, and fourth fasteners can include at least onemagnet and/or at least one mechanical fastening element, such as amechanical element configured to penetrate and engage with tissue. Inaddition, the method can include using at least one magnet deliveredthrough a catheter to guide at least one of the fasteners into position.As one option, the guiding magnet may be removed after guiding thefastener or fasteners into position. The fastener or fasteners may bedelivered through the guiding magnet.

In another general aspect of the invention, a heart valve annulus ismodified by delivering a first fastener through a catheter into thecoronary sinus, and delivering a second fastener through a catheter toat least one of two locations, the two locations being 1) generallyabove the annulus in the left atrium, and 2) generally below the annulusin the left ventricle. The fasteners are secured to the annulus and thedistance between the first and second fasteners is reduced to therebymodify the annulus with the respectively delivered fasteners. In anotheraspect, a flexible tensile member is connected between the fasteners,and the distance between the fasteners is reduced by tensioning theflexible tensile member to modify the annulus. The flexible tensilemember may be locked into position with respect to the fasteners byapplying a crimp member or other locking element, which may or may notbe part of a fastener, to the flexible tensile member. In anotherembodiment, the fasteners are held in spaced apart positions whilesecuring the fasteners to heart tissue at the two locations. Thefasteners are biased toward each other to reduce the distance betweenadjacent fasteners and modify the annulus with the respectivelydelivered fasteners. Biasing the fasteners can further comprisemagnetically attracting adjacent fasteners toward one another or, asanother example, spring biasing adjacent fasteners toward one another.As one option, pressurized air may be used to hold the fasteners in thespaced apart positions prior to biasing the fasteners together. Inanother aspect, radio frequency energy or any other suitable method isused to form an aperture in the heart tissue in order to apply thefastener(s) through the tissue.

The invention further provides a system for modifying an annulus of aheart valve comprising a first catheter, a first magnet coupled with thefirst catheter in such a manner that the first catheter is operative todeliver the first magnet adjacent to the annulus. The system furtherincludes a second catheter and a second magnet coupled with the secondcatheter in such a manner that the second catheter is operative todeliver the second magnet adjacent to the annulus. A fastener deliveryportion may be operatively associated with the first catheter. Thefastener delivery portion may be coupled at predetermined angle relativeto an axis of magnetic attraction between the first and second magnets.

The fastener delivery portion can be movable relative to the first andsecond magnets so as to enable delivery of a fastener to a desiredposition. The system can further comprise a plurality of fastenerdelivery portions configured to deliver respective fasteners at spacedapart locations along the annulus. The plurality of fasteners may becoupled together with at least one flexible tensile member such that theflexible tensile member is capable of drawing the fasteners together andthereby modifying the annulus.

In another embodiment, a catheter system for modifying an annulus of aheart valve comprises a catheter having at least one lumen and first andsecond fasteners coupled together by an elongate flexible member suchthat the first fastener is movable along the elongate flexible member toa position closer to the second fastener. An actuation device is coupledin a releasable manner to the elongate flexible member and adapted topull the elongate flexible member to thereby reduce the distance betweenthe first and second fasteners. A coupling secures the elongate flexiblemember in a locked position relative to the first and second fasteners.The first and second fasteners can further comprise magnets and/ormechanical fasteners, such as fasteners having projections configured topenetrate heart tissue. The coupling further can further comprise acrimpable or other type of locking member. The first and secondfasteners may be further coupled together by a length adjustable memberconfigured to allow the distance between the first and second fastenersto be shortened as the actuation mechanism pulls the flexible tensilemember. The length adjustable member can include first and secondtelescoping portions coupled together or, as another example, agenerally accordion-shaped section.

In another embodiment, a catheter system for modifying an annulus of aheart valve comprises a catheter having at least one lumen and first andsecond fasteners coupled together by a flexible tensile member such thatthe first fastener is movable along the flexible tensile member relativeto the second fastener. A first fastener delivery portion is coupledwith the catheter and delivers the first fastener into a first positionproximate the annulus. A second fastener delivery portion is coupledwith the catheter and moves with respect to the first fastener deliveryportion. The second fastener delivery portion delivers the secondfastener into a second position proximate the annulus and spaced fromthe first position. This system can further include a third fastenercoupled to the flexible tensile member, and a third fastener deliveryportion coupled with the catheter and capable of delivering the thirdfastener into a third position proximate the annulus and spaced from thefirst and second positions. The system can also include first and secondfastener drive members coupled respectively with the first and secondfastener delivery portions, and being selectively movable to drive thefirst and second fasteners into the tissue proximate the annulus.

The systems of this invention can include fastener delivery portionscomprising at least one spring and drive member each located, forexample, at the distal end of a catheter device. Such fastener deliveryportions can force the fastener(s) into tissue proximate the annulus.Catheters used in the invention can include a magnet at the distal endfor coupling with another magnet located proximate the annulus therebystabilizing the catheter during delivery of the fastener(s). A lockmember may be secured to the flexible tensile member and used toselectively prevent relative movement between the delivered fasteners.

In another embodiment, a catheter system for modifying an annulus of aheart valve includes a catheter having at least one lumen and first andsecond fasteners coupled together by a flexible tensile member andadapted to be secured to heart tissue proximate the annulus. A rod ismovable between a compact state within the lumen and an expanded stateoutside of the lumen. The first and second fasteners are further coupledto the rod such that the first fastener is movable along the rodrelative to the second fastener by applying tension to the flexibletensile member. The rod may be generally C-shaped in the expanded stateso as to follow the annulus. A third fastener may be coupled formovement along the rod and adapted to be secured to heart tissueproximate the annulus. A second flexible tensile member can be securedto the third fastener. The third fastener may then be moved along therod relative to the second fastener by applying tension to the secondflexible tensile member. A magnet can be connected to the rod andadapted to magnetically couple with a magnet in the coronary sinus forstabilizing the position of the rod as the fasteners are secured to theheart tissue.

Another catheter system for modifying an annulus of a heart valvegenerally comprises a catheter having at least one lumen and first andsecond fasteners adapted to be secured to heart tissue proximate theannulus. At least one flexible tensile member couples the first andsecond fasteners together. A locking device activated by way of acatheter to fix the fastener positions is provided. For example, alocking element delivery device is deployable through a catheter, whichmay be the same catheter as a fastener delivery catheter, or a differentcatheter. For example, the locking element can be a crimp and acompression applying mechanism deployed from the catheter can beconfigured to compress the crimp onto the flexible tensile member afterthe fasteners are pulled toward one another with the flexible tensilemember to modify the annulus. Other types of locking elements may, forexample, include spring elements or other biased elements which are heldin an open position and then released into a closed or locked positiononto one or more flexible tensile members. Any locking element which isselectively lockable onto a flexible tensile member may be used asappropriate for the application. A flexible tensile member releasingdevice is provided which releases the flexible tensile member from thecatheter system is also provided. This may involve a mechanicaldisconnection mechanism, such as threads or other connectors, or acutting mechanism associated which cuts the flexible tensile memberafter locking takes place, such as mentioned above. A third fastener isadapted to be secured to the heart tissue, and separate flexible tensilemembers may be connected with each of the fasteners and threaded throughthe locking element, such as a crimp. It will be appreciated that theterm “flexible tensile members”, as used herein, will apply to separateportions of a single element, such as a suture strand, wire, cable orother solid or hollow elongate structure which may be looped back onitself and locked in place, and it will also apply to separate elementsaltogether.

Another catheter system for modifying an annulus of a heart valvecomprises first, second and third fasteners adapted to be secured toheart tissue proximate the annulus. First, second and third flexibletensile members are respectively connectable to the first, second andthird fasteners. A generally V-shaped valve support member is providedhaving a pair of legs movable between a compact state suitable farcarrying the valve support member within a catheter and an expandedstate in which the legs are more separated. A free end of each legincludes respective first and second eyelets receiving the first andsecond flexible tensile members and an apex between the pair of legsincluding a third eyelet receiving the third flexible tensile member.First, second and third crimp members may be provided for respectivelysecuring the first, second and third flexible tensile members withrespect to the first, second and third eyelets after at least one of theflexible tensile members is pulled tight to modify the shape of theannulus.

Various additional features, advantages, and aspects of the inventionwill become more readily apparent to those of ordinary skill in the artupon review of the following detailed description of the illustrativeembodiments taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a cutaway of the left side of the heart showing the internalmuscular and valve structure.

FIG. 1B is a top view showing the normal positions of a mitral valve andadjacent aortic valve.

FIG. IC is a top view similar to FIG. 1B but illustrating the mitralvalve in a prolapsed condition in which the posterior leaflet isseparated from the anterior leaflet.

FIG. 1D is an elevational view illustrating a conventional annuloplastyring,

FIG. 1E is a top view similar to FIG. 1B, but illustrating theattachment of the annuloplasty ring to the mitral valve annulus.

FIG. 1F is a top view of the mitral valve illustrating an Alfieri stitchtechnique for reducing the gap between the posterior and anteriorleaflets.

FIG. 1G is a top view of the mitral valve illustrating another suturingtechnique which has been used to close the gap between the posterior andanterior leaflets.

FIG. 1H is a cross sectional view of the heart anatomy illustrating thecoronary sinus (CS) running behind the posterior leaflet of the mitralvalve.

FIG. 1I is a cross sectional view of the heart anatomy similar to FIG.1H, but illustrating a technique for inserting anchors into the CS usinga catheter based system.

FIG. 1J is a cross sectional view of the heart anatomy similar to FIG.1I but illustrating an improved catheter based procedure for insertinganchors into the CS and correcting for mitral valve insufficiencyaccording to the invention.

FIG. 1K is an enlarged view of the connector placed in accordance withthe invention through the CS and the annulus tissue of the mitral valve.

FIG. 2A is a cross sectional view of the mitral valve illustrating theposterior and anterior leaflets and the relative position of the CS withrespect to the valve annulus.

FIG. 2B is a view similar to FIG. 2A and illustrating the effect ofcinching or pulling the CS toward the mitral valve opening at a locationwhich is above the level of the valve annulus.

FIG. 2C is a view similar to FIG. 2B, but illustrating the placement ofa fastener in accordance with the invention to bring the level of the CScloser to the annulus before cinching.

FIG. 3 is a cross sectional view of the heart anatomy, on the left sideof the heart, illustrating a catheter based system according to theinvention.

FIGS. 3A-3D illustrate a progression of steps in a catheter based methodfor correcting a mitral valve insufficiency in accordance with theinvention.

FIGS. 4 and 5 illustrate a cross section of the mitral valve in whichanchors have been daisy chained together and then cinched to close thegap between the leaflets of the valve.

FIGS. 6A-6E-1 illustrate a cross section of the heart anatomy throughthe CS and illustrating a pair of catheter devices being used tosuccessively apply fasteners in a daisy chained fashion and both cinchand lock the fasteners in place.

FIGS. 6F and 6F-1 illustrate the final locked positions of thefasteners, flexible tensile member and locking member placed viacatheters.

FIGS. 7A-7G are enlarged cross sectional views of the mitral valve atthe valve annulus taken generally along line 7-7 of FIG. 6A and showingthe placement of a fastener from the CS downwardly through the valveannulus to the underside or left ventricle side of the valve.

FIGS. 8A and 8B illustrate cross sectional views, respectively, throughthe CS and illustrating the use of a pair of magnets in the CS formagnetically guiding and locking up with a magnet on an anchor deliverycatheter.

FIG. 8C is an enlarged view of the various magnets and their magneticfields.

FIG. 9 is a cross sectional view of the heart anatomy through the CS,and illustrating the use of electromagnets in a catheter device.

FIG. 10 is a cross sectional view of the heart anatomy through the CSand illustrating the successive positioning of a catheter devicerelative to another catheter device in the CS through the use ofmagnets.

FIGS. 11A and 11B illustrate cross sectional views of the heart anatomythrough the CS and respectively illustrating nonactivated and activatedpositions of a series of magnetic fasteners used for correcting a mitralvalve insufficiency.

FIGS. 11A-1 and 11B-1 respectively illustrate enlarged views of themagnetic fastener system in its nonactivated and activated states.

FIG. 11C is a cross sectional view through the mitral valve and CSillustrating the final activated position of the fastener system placedin accordance with FIGS. 11A and 11B.

FIGS. 12A and 12B illustrate an alternative in which the magneticfasteners are placed respectively in the CS and in the left atrium.

FIGS. 13A and 13B are cross sections of the heart anatomy through the CSand illustrating an additional magnetic fastener placed below theannulus in left ventricle to assist with reducing the mitral valveinsufficiency.

FIGS. 14A and 14B are cross sections through the CS and mitral valve andillustrating another alternative magnetic fastening system.

FIG. 14C is similar to FIG. 14B, but illustrates a magnetic fastenerwith additional mechanical fastening elements in the form of projectionswhich engage and penetrate tissue proximate the valve annulus.

FIGS. 14D and 14E are perspective views illustrating the magneticfastening elements with mechanical tissue engaging projections.

FIGS. 15A-15C are cross sections through the CS and mitral valveillustrating an alternative fastener delivery mechanism in which afastener is delivered through a catheter and also through magneticguiding elements.

FIGS. 15D and 15E are cross sections similar to FIG. 15A, butillustrating a series of fasteners delivered through magnetic guidingelements and daisy chained together using a flexible tensile member.

FIGS. 16A-16C are cross sectional views similar to FIGS. 15A-15C, butillustrating the use of magnetic guiding elements which have separableportions.

FIGS. 16A-1 and 16A-2 are perspective views of the magnetic guidingelements respectively shown in nonseparated and separated positions.

FIGS. 16D and 16E are similar to FIGS. 15D and 15E, and illustrate thedaisy chained connection of the fasteners with the magnetic guidingelements removed.

FIG. 17 is a perspective view showing a fastener delivery mechanism on acatheter which includes a magnetic guiding element magnetically coupledto a second magnetic guiding element of a second catheter.

FIGS. 18A-18C respectively illustrate cross sectional views of the heartanatomy through the CS and the mitral valve and the placement of analternative catheter delivered fastening system.

FIG. 19A is a cross sectional view of the heart anatomy through the CSand the placement of another alternative catheter delivered fasteningsystem.

FIGS. 19B and 19C illustrate the daisy chained fasteners of FIG. 19Arespectively before and after cinching of the fasteners to shorten thevalve annulus.

FIGS. 20A and 20B illustrate a cross sectional view of tissue receivingfasteners formed from shape memory alloy both before and afteractivation of the shape memory effect to shorten the overall length ofthe tissue engaged with the fasteners.

FIG. 21A is a cross sectional view of the heart anatomy through the CSand illustrating the use of a catheter to delivery a series of fastenersin the form of tissue penetrating fasteners separated by pledgets alonga flexible tensile member.

FIGS. 21B-21D respectively illustrate enlarged views of the fastenerdelivery system shown in FIG. 21A as well as the final cinching thereof.

FIG. 22 illustrates an alternative system to FIGS. 21A-21D in which asecondary cinching mechanism is provided in the form of a secondflexible tensile member.

FIGS. 23A-23E illustrate respective cross sections of the heart anatomythrough the CS and the use of another alternative catheter based systemfor serially delivering fasteners coupled with a flexible tensile memberused to cinch valve tissue and correct a mitral valve insufficiency.

FIGS. 24A-24C are respective cross sections through the heart anatomyincluding the CS above the mitral valve and illustrating anotheralternative catheter based fastener system.

FIGS. 25A-25D illustrate an enlarged cross section of the catheter basedsystem of FIGS. 24A-24C, and showing the cinching and locking thereof.

FIGS. 26A-26C illustrate another alternative cinching and locking systemfor a catheter based fastener system similar to FIGS. 25A-25D.

FIGS. 27A-27B illustrate yet another alternative cinching and lockingmechanism associated with a catheter based fastener system similar toFIGS. 26A-26C.

FIGS. 28A and 28B are respective cross sections similar to FIGS. 27A and27B, but illustrating another alternative fastening system.

FIGS. 29A and 29B illustrate respective cross sections of yet anothercatheter based fastening system.

FIG. 30 illustrates a cross section of yet another catheter basedfastener system.

FIG. 31A is a cross section taken along line 31A-31A of FIG. 30.

FIG. 31B is a cross section taken along line 31B-31B of FIG. 30.

FIGS. 32A and 32B illustrate another alternative fastening system in itsnonactivated and activated states.

FIG. 32C is a cross section taken along line 32C-32C of FIG. 32A.

FIG. 33 is a cross section of another alternative fastening system.

FIGS. 33A and 33B are enlarged cross sectional views of portions of FIG.33 respectively shown in nonactivated and activated states.

FIGS. 34A-34I are respective cross sections of the heart anatomysuccessively showing the use of another alternative catheter basedfastening system.

FIG. 35A is a cross section taken through the CS and illustrating aperspective view of another alternative catheter based fastener deliverydevice.

FIGS. 35B-35E are respective cross sections of the fastener deliverydevice shown in FIG. 35A and used to deliver multiple fasteners coupledto a flexible tensile member.

FIG. 35F is a cross sectional view of the fastening system delivered,cinched and locked to shorten the length of tissue engaged with thesystem.

FIG. 36 is a perspective view of the distal end of another alternativecatheter based fastener delivery system.

FIG. 37A is a fragmented view of the distal end of another catheterbased system for delivering a fastener and valve support member of theinvention.

FIGS. 37B and 37C respectively illustrate the deployed valve support andfastener system on the mitral valve.

FIGS. 38A-38I respectively illustrate cross sections of the mitral valveand CS and the progression of using another catheter based fastenerdelivery system.

FIGS. 39A and 39B respectively illustrate cross sections of the distalend of a crimping and cutting device which may be used with variouscatheter based systems of this invention.

FIGS. 40A-40D respectively illustrate cross sections through the heartanatomy including the mitral valve and CS, and illustrating anotheralternative catheter based fastener delivery system.

FIGS. 41A-41C illustrate another catheter based fastener deliverysystem.

FIG. 42A illustrates an elevational view of one exemplary fastenerusable in the systems described herein.

FIG. 42B is a cross sectional view taken along line 42B-42B of FIG. 42A.

FIG. 43 is a side elevational view of another alternative fastenerhaving a curved shape.

FIGS. 44A-44C respectively illustrate the use of another alternativefastener suitable for the systems of the present invention.

DETAILED DESCRIPTION

In this description of illustrative examples, like reference numeralsrefer to like element throughout the drawings. Like reference numeralswith prime (′) marks or double prime (″) marks refer to like structureexcept for minor differences which will be apparent. FIGS. 1J and 1Killustrate an improved catheter delivered fastener system 50′ whichinvolves placing a permanent fastener or anchor 60 from the CS 46through the wall of the left atrium 12 proximate annulus 40 foranchoring purposes. This improvement may be applied to the priorcinching method illustrated in FIG. 1I discussed above. The fastener 60may be deployed and anchored in various manners, including thosediscussed further below. Because the fastener 60 extends not onlythrough the delicate CS tissue, but also through the thicker tissue ofthe left atrium 12, secured anchoring takes place and, upon cinchingusing a flexible tensile member 54, the annulus 40 may be reduced tocorrect for a prolapsed valve or other mitral valve insufficiency withless risk of tearing tissue. FIGS. 2A and 2B illustrate the anatomicalrelationship between the CS 46 and the mitral annulus 40. In particular,the CS 46 can be noncoplanar with the mitral annulus 40, causing CSbased cinching approaches to the inefficient to effectively modify theshape of the annulus 40. In many cases, the CS 46 extends above themitral annulus 40 along the left atrial wall and, instead of pulling theannulus 40 toward the valve opening or gap 32, the left atrial wall isinstead pulled inwardly as shown in FIG. 2B. This causes more of arestriction of the atrium 12 above the valve 20, rather than a reductionof the annulus 40 itself and, therefore, prevents a complete correctionof the valve insufficiency in this case. In an approach which is similarto the approach shown in FIGS. 1J and 1K, but having additionalbenefits, a fastener or anchor 62 extends from the CS 46 into the leftventricle side of the annulus 40. This plicates the tissue between theCS 46 and the left ventricle 14 thereby bringing the CS 46 closer toand/or more in line with the annulus 40. Once this plication has takenplace as shown in FIG. 2C, a CS cinching device can more efficiently andeffectively reduce the mitral annulus 40. That is, when cinched towardthe valve opening or gap 32, the cinching device, which is more in linewith the valve annulus 40, can better pull the posterior leaflet 24toward the anterior leaflet 22 thereby closing the gap 32 between theleaflets.

As shown in FIGS. 3, 3A and 3B, a pair of magnetically attractivecatheters 64, 66 can be used in concert with each other using the CS 46as an approximate guide to locate and position the tip of anothercatheter or catheter portion at the mitral annulus 40. Morespecifically, as one example, one catheter 66 includes both a magneticguiding portion 66 a and an anchor delivery portion 66 b positioned in apredetermined manner, such as at a predetermined acute angle relative tothe magnetic portion 66 a. Another catheter 64 is placed in the CS 46and includes a magnetic guiding portion 64 a. The two magnetic guidingportions 64 a, 66 a magnetically couple with one another to lock up theposition of the anchor delivery catheter portion 66 b at a predeterminedangle which will properly deliver a fastener or anchor 68 into a desiredportion of the tissue. As shown in FIG. 3A, the magnetically lockedcatheters 64, 66 can deliver a first loop type anchor or fastener 68through the valve annulus 40 on a skewed or otherwise known trajectoryfrom the axis of magnetic attraction, such that the loop type anchor orfastener 68 is accurately placed, for example, through the annulus 40from the left ventricle side to the left atrium side of the mitral valve20. As shown in FIG. 3B, the CS catheter 64 can be translated to adifferent position within the CS 46 causing the magnetic tip 66 a of theleft ventricle catheter 66 to follow along the annulus 40 wheresubsequent loop type anchors or fasteners 68 may be placed in a similarfashion to the first applied anchor or fastener 68. FIG. 3C illustratesthat a loop type fastener or anchor 68 may capture a T-bar type anchoror fastener 70 passing from the CS 46 through the left atrial wall usinga catheter delivery system 72 guided within the CS 46. In thisembodiment, fasteners 68 are therefore placed from the left ventricle 14into the left atrium 12, and additional connecting fasteners 70 areplaced from the CS 46 into the left atrium 12 for engagement with theother fasteners 68. As shown in FIG. 3D, multiple loop and T-bar anchorsor fasteners 68, 70 may be cinched together with a flexible tensilemember 74 similar to a drawstring-type configuration, resulting inalignment of the CS 46 and the annulus 40 into a more coplanarrelationship at several locations. The cinching or drawstring actiontherefore closes the gap 32 between the posterior leaflet 24 and theanterior leaflet 22 in a more even and effective manner. FIG. 4illustrates magnetically attractive catheter portions 64 a, 66 arespectively in the CS 46 and under the mitral annulus 40 used todeliver a series of anchors or fasteners 76 with a T-bar shape from theleft ventricle side of the mitral valve 20 to the left atrium side ofthe mitral valve 20. As also shown in FIG. 4, the T-bar shaped anchorfasteners 76 are delivered in a daisy chained fashion from catheterportion 66 b such that a second catheter 78 may be used to cinch adrawstring or flexible tensile member 80 to shorten or reduce the valveannulus 40. As shown in FIG. 5, the anchors or fasteners 76 may becinched together using the drawstring or flexible tensile member 80within catheter 78 to pull the posterior leaflet 24 toward the anteriorleaflet 22. The flexible tensile member 80 is then locked in place orotherwise secured to retain the fasteners 76 in their new positions,such as in one of the manners described below.

FIGS. 6A-6F respectively illustrate catheters 82, 84 being placed intothe heart 10 through the aortic valve into the left ventricle 14 andthrough the CS 46 generally adjacent the valve annulus 40. This top viewof the heart 10 shows how a first T-bar type anchor or fastener 86having a tail, forming a flexible tensile member 88, is loaded into theCS catheter 84 at the proximal end 84 a so that it may be pushed down tothe distal tip 84 b to be in position for delivery. The position of theleft ventrical catheter 82 with a magnetic tip 82 a is also showngenerally opposite to the distal tip 84 b of the CS catheter 84. Asshown in FIG. 6B, a second anchor or fastener 90 is delivered in a daisychain fashion by running an eyelet 90 a on the second anchor 90 over thetail or flexible tensile member 88 associated with the first anchor 86.FIG. 6C illustrates the second anchor 90 of the daisy chain deliveredthrough the valve annulus 40 at a spaced apart location from the firstanchor 86. FIG. 6D illustrates a third anchor 92 at the annulus 40similarly delivered along flexible tensile member 88 using an eyeletportion 92 a. Anchor 92 is threaded through the CS catheter 84 anddriven through the tissue generally at the valve annulus 40. In the caseof this type of anchor, respective transverse bar portions 86 b, 90 b,92 b of the anchors or fasteners extend into the left ventricle 14. FIG.6E illustrates a locking member 94, including a crimp 96 delivered overthe daisy chain tail or flexible tensile member 88 within the proximalCS 46. Locking member 94 is shaped or otherwise configured to hold itsposition within the CS 46. FIG. 6E-1 illustrates the crimp 96 beforecrimping onto the flexible tensile member or tail 88. As shown in FIGS.6F and 6F-1 a catheter device 98, which may be deployed through asuitable delivery catheter (not shown) may be used to pull the flexibletensile member 88 thereby cinching the assembly and pulling theposterior leaflet 24 toward to the anterior leaflet 22. Once thiscinching is accomplished, the crimp is crimped against the flexibletensile member 88 adjacent to the lock member 94 to keep the assembly atthe desired position.

FIG. 7A illustrates how magnetically attractive portions 82 a, 84 b ofthe LV and CS catheters 82, 84 should be strongly attracted when the gapdistance (d1) is relatively short. If this gap distance d1 is notrelatively short, then other methods of increasing the lock up force maybe necessary as further described herein below.

FIGS. 7B and 7C illustrate how a T-bar type anchor or fastener 86 wouldbe pushed from an opening 84 c in the CS catheter through the tissuefrom the CS 46 into the left ventricle 14 until it is fully deployedacross the tissue. FIG. 7D illustrates a larger gap d2, through whichtwo magnetic portions 82 a, 84 b of the respective LV and CS cathetersmay magnetically couple, depending on the magnetic attractive forcesdeveloped. In FIGS. 7E and 7F, the magnetic catheter in the LV 14 hasnot been illustrated (only for purposes of clarity), such that thedelivery of a T-bar type fastener or anchor 86 may be shown in its fullydeployed state across the tissue. As shown in FIG. 7F, the T-bar portionor transverse portion 86 b of the fastener 86 self-rotates in order tofit snugly along the annulus 40 under the posterior leaflet 24. In FIG.7G, the relative position of the CS 46 to the annulus 40 is improvedafter cinching of the anchor 86 plicates the tissue between the annulus40 and the CS 46 as previously described.

FIGS. 8A-8C illustrate that multiple magnets 102 a, 102 b may be used inthe CS, such as on a CS catheter 102, to attract an opposite magnet poleat the tip 100 a of the LV catheter 100. This allows the LV catheter 100to be steered in three axes to deliver a fastener through a secondcatheter portion 100 b into the annulus 40. It will be appreciated thatmultiple magnets may also or alternatively be used in the LV 14 and/orin the LA for steering purposes and/or additional magnetic force. FIG.8C illustrates in detail how a pair of magnets 102 a, 102 b in the CS 46mounted such that like poles are facing each other results in a 360°magnetic field which attracts the opposite pole of a magnetic cathetertip 100 a within the LV 14. This can eliminate the need to rotationallyorient the CS catheter 102 so that its pole is facing an opposite polein the LV 14. FIG. 9 illustrates the use of electromagnets 104 in a CScatheter 106 which may be used in conjunction with or as replacementsfor permanent magnets as described in the above embodiments. It willalso be appreciated that one element which generates magnetic forces maybe used in conjunction with another element which is magneticallyattracted to the magnetic force generating element, but not necessarilya magnetic force generating element itself. For example, anelectromagnet or permanent magnet may be positioned on one side of thetissue to be anchored, and another element formed from ferrous metal maybe positioned on the opposite side of the tissue for magnetic couplingpurposes while a fastener or anchor is driven into the tissue.

FIG. 10 illustrates a CS catheter 108 configured with multiple oppositepole magnetic pairs 110, 112 along its length and a steerable LVcatheter that may be directed to each discrete pair of magnets 110, 112to delivery anchors or fasteners (not shown), such as in one of themanners previously described.

Now referring to FIGS. 11A, 11A-1, 11B and 11B-1, a CS catheter 116 maybe configured with multiple discrete magnets 118 along its length,wherein the poles of the magnets 118 are arranged such that they aremagnetically attracted to each other, yet kept apart by a restrainingforce, such as pressurized air directed to a bladder-like structure 120between the magnets 118. In this case, the magnets 118 are being used asfasteners to fasten or trap tissue therebetween. A similar catheter 122delivers magnets 124 on an opposite side of the tissue, such as withinthe LV 14. When the restraining force is removed, such as by reducingthe air pressure as shown in FIGS. 11B and 11B-1, the magnets 118 areattracted to each other and thereby modify the valve annulus 40 suchthat the posterior leaflet 24 is pulled toward the anterior leaflet 22.As shown best in FIGS. 11B and 11C, each strip of magnets 118, 124 hasopposing poles along its length and thereby plicates the tissue byremoving a restraining force between the magnets 118 in the CS 46,thereby allowing the attracted magnets 118 to move toward each other andplicate the annulus tissue therebetween. The magnets 124 in the LVcatheter 122 may be configured in the same manner as magnets 118.

FIGS. 12A and 12B illustrate respective strips of magnets 118, 124, asdescribed in connection with FIGS. 11A-11C in the CS 46 and the LA 12instead of the LV 14. The two strips of respective magnets 118, 124align with each other such that the magnets 118, 124 are anchored toeach other across the left atrial wall. In this case, once again, thestronger-atrial wall is used as the anchoring tissue, as opposed to theCS tissue only. When the magnets 118 in the CS 46 are brought together,as discussed above, an annular reduction of the mitral annulus 40 isachieved similar to the manner discussed above.

FIGS. 13A and 13B illustrate strips of magnets 118, 124 in the CS 46 andLA 12 as discussed previously. However, cinching via the CS 46 alone maynot have sufficiently precise pull on the mitral annulus 40 since thesetwo anatomical structures typically do not lie at the same level. Eventhe two strips of magnets 118, 124 shown in FIG. 12B are only coupledacross the left atrial wall, and this may not be in line with theannulus 40 at all locations. Therefore, an additional magnet 126 shownin FIGS. 13A and 13B, fixed to a metal or otherwise substantially rigidcurved bar 128, is placed under the mitral valve 20 in the LV 14, suchthat magnet 126 locks up with the strip of magnets 118 in the CS 46.This pulls the exterior annulus 40 toward the CS 46 and establishes amore coplanar relationship.

FIG. 14A illustrates a modification of the strip of magnets 124positioned in the LA 12 such that there is an extension magnet 130 whichis positioned at the midpoint of the strip of magnets 124. Thisextension magnet 130 extends down to the mitral valve annulus 40bridging the gap between the CS 46 and the valve annulus 40. This maypull a magnet 132 and curved support bar 134 under the valve 20 tighterto the CS 46, as shown in FIG. 14B. It will be appreciated that magnet132 and support bar 134 are similar to magnet 126 and support bar 128,except that bar 134 has a fabric covering 136 as may be desired fortissue ingrowth purposes. FIGS. 14C-14E illustrate the use of additionalmechanical fasteners such as projections 138 on one or more of themagnets 132 used in the embodiments described above. This can applyadditional traction or fastening to the tissue than could otherwise besupplied by the use of magnets alone.

FIGS. 15A-15E comprise a series of illustrations showing anotheralternative catheter based fastener delivery system. In addition toshowing the use of a fastener 140 to pull the CS 46 into a more coplanarrelationship with the annulus 40 (FIG. 15C), this system utilizesmagnets 142, 144 which have orifices 142 a, 144 a through which thefastener 140 is delivered such that more precise placement of thefastener 140 may be obtained in certain instances while also using amagnetic lock up force for more positively driving the anchor orfastener 140. It will be appreciated that magnet 144 will be coupled toa catheter (not shown) for positioning within the CS 46. Magnet 142 maybe releasably coupled to a steerable catheter 146. As shown in FIGS. 15Dand 15E, after a plurality of magnets 142, 144 and fasteners 140 havebeen delivered such that tissue is trapped therebetween, a flexibletensile member 148 and crimps 150 may be used to cinch and lock thefasteners 140 together thereby pulling the posterior leaflet 24 towardthe anterior leaflet 22 and closing a gap 32 in the valve 20.

FIGS. 16A-16E, as well as FIGS. 16A-1 and 16A-2 illustrate a systemwhich is the same as the system shown in FIGS. 15A-15E, except that themagnets 142′, 144′ are formed of separable portions, such as halves 142a, 142 b, 144 a, 144 b, so that the magnets 142′, 144′ may be removedafter the fasteners 140′ have been properly delivered. Thus, the anchorsor fasteners 140′ themselves have portions 140 a, 140 b which retain thefasteners 140′ in place across the tissue proximate the annulus 40, andportions 140 b accept a flexible tensile member 148 and crimps 150 forcinching and locking purposes as shown in FIGS. 16D and 16E generally inthe manner or manners described herein. The separable magnet portions142 a, 142 b and 144 a, 144 h may be coupled to suitable catheterdevices allowing their release from fasteners 140′ and withdrawal fromthe patient.

FIG. 17A illustrates an alternative fastener delivery system 160 usingmagnetic guidance in which the fastener 140′ is not delivered throughthe magnets 162, 164, but is delivered adjacent to the magnets 162, 164in a fastener driving portion 166 of a catheter 168. This is anothermanner of using magnetic guidance and temporary lock up without thenecessity of leaving the magnets 162, 164 in place after completion ofthe procedure.

FIGS. 18A-18C illustrate a more conventional annuloplasty that may beaccomplished using magnetic guidance and lock up in a temporary mannerto facilitate fastener placement and driving. More specifically, amagnetic strip 170 is placed into the CS 46 using a catheter 172. Asecond magnetic strip 174 with a fabric covering 176 is placed in theleft atrium 12 also via a catheter 178. Fasteners 180 are placed intothe fabric 176 on the strip 174 in the left atrium 12 from theundersurface of the mitral valve 20 again using a catheter 82. Likewise,fasteners 180 are driven through the CS 46 and left atrium wall into thefabric 176 in a manner similar to that described with respect to, forexample, FIGS. 3C and 3D through a catheter with a sideward firingfastener driving portion (see also FIGS. 7D-7F). The magnetic strips170, 174 are removed from the fabric covering 176 and from the CS 46 andthe fabric 176 is then drawstringed or cinched with a suitable flexibletensile member 184 coupled therewith to produce annuloplasty or pullingof the posterior leaflet 24 toward the anterior leaflet 22 to eliminateor reduce a gap 32 in the mitral valve 20.

FIGS. 19A-19C illustrate one alternative to a T-bar configuration offasteners as previously described. In this embodiment, fasteners 190 inthe form of anchor buttons 190 a are placed below the mitral valve 20along the annulus 40 using catheters 192, 194 with magnetic guidance andlock up as previously described. Although not shown, another catheter isused in the left atrium to deliver buttons 190 b which couple withbuttons 190 a. Buttons 190 a are further coupled to a flexible tensilemember 196 which may be secured with crimps 200 (one shown in FIG. 19C)as previously described. This compresses the mitral tissue betweenrespective tissue engaging portions of the buttons 190 a, 190 b. Thebuttons 190 a, 190 b are drawstringed or cinched from below usingflexible tensile member 196 threaded through respective eyelet portions198 of each button 190 a.

FIGS. 20A and 20B illustrate another way to plicate the annulus 40 byusing memory alloy staples 202 driven into the tissue along the annulus40. When the memory alloy activates, the staples 202 shorten and plicatethe tissue (FIG. 20B) to shorten the annulus 40 of the mitral valve 20to pull the posterior leaflet toward the anterior leaflet as generallydescribed above.

FIGS. 21A-21D illustrate the placement of fasteners 210 on the leftatrial side of the mitral valve 20, daisy chained to pledgets orfasteners 212 in the form of tissue trapping load spreading membersunderneath the annulus 40. These fasteners 210, 212 are coupled togetherby a flexible tensile member 214 or drawstring, in this case. FIGS.21A-21C illustrate a catheter 216 which delivers fasteners 210, 212 in aserial fashion along flexible tensile member 214 such that fasteners 210are driven through the tissue and fasteners or pledgets 212 are releasedbetween each fastener 210. The series of fasteners 210, 212 is thendrawn together using the drawstring or flexible tensile member 214 asshown in FIG. 21D. This shortens the distance between each of thefasteners 210, 212 and the entire structure with elements above andbelow the annulus 40. The tissue becomes trapped between the fasteners210, 212 spreading loads over larger areas and reducing tear out risks.

FIG. 22 illustrates a modified version of the system illustrated inFIGS. 21A-21D. In this embodiment, after the first drawstring 214 ispulled to tighten the various fasteners 210, 212′ and plicate theannulus 40 as generally shown in FIG. 21D, a second drawstring 218coupled to eyelets 220 each of the pledgets 212′ may be pulled for asecondary shortening operation which further reduces the annulus 40, asnecessary.

FIGS. 23A-23E illustrate an alternative embodiment which is similar toFIGS. 21A-21D, except that the pledgets 212″ have a pair of holes 222,224 through which the flexible tensile member 214 or drawstring isthreaded, as opposed to an eyelet structure.

FIGS. 24A-24C illustrate another embodiment of a catheter based fastenersystem 230 which employs a series of connected magnets 232, 234 with oneseries of magnets 232 lying in the CS 46 lying adjacent to the mitralvalve annulus 40 and another series 234 lying in the LV 14 adjacent tothe annulus 40. The magnets 232 residing in the CS 46 are coupledtogether by coil springs 236 and by a flexible tensile member 238, whilethe magnets 234 in the LV 14 are, in one embodiment, positionedindividually in the LV adjacent to magnets in the CS 232, after releasefrom the LV magnet delivery catheter 240, as shown in FIG. 24C. Inanother embodiment, the array of LV magnets 234 is shown in FIG. 24Aadjacent to the CS magnets 232 and connected by a member consisting of asheath 233 upon which the magnets 234 can slide. The array of magnets234 and the sheath 233 are deposited in the LV 14 as the deliverycatheter 240 is withdrawn. The connecting sheath 233 prevents the riskof an embolic accident resulting from a detachment of a single magnet234. In FIG. 24B, the withdrawal of the LV delivery catheter 240 isshown in more detail. The most distal magnet 234 is shown attached tothe sheath 233, whereas the next more proximal magnet 234 is still onthe shaft of the delivery catheter 240. Each series of magnets 232, 234is introduced into the positions shown in FIGS. 24A-24C by respectivecatheters 242, 240. A coupling 244 is provided and is releasably coupledto a pull wire or cable 246 in the catheter 242 such that the series ofmagnets 232 may be cinched or drawn together to reduce thecircumferential length of the valve annulus 40. The LV magnets 234,owing to their attraction to their CS counterparts 232, are thus pulledtogether to accomplish plication of the dorsal cusp of the mitral valve20 adjacent to the annulus 40. Plication may be better facilitated byfeatures on the surface of the CS magnets 232 which grip the endocardialsurface, and promote ultimate tissue ingrowth about the magnets 232 tostrengthen the plication. Once the reduction has taken place, themagnets 232 are locked in place, and the catheter 242 is removed.

Referring more specifically to FIGS. 25A-25D, the operation of thecoupling 244, and a release and locking mechanism 250 is shown. Theinitial position is shown in FIG. 25A in which the magnets 232 arespaced apart by the uncompressed coil springs 236 and the flexibletensile member 238 which is fixed to a coupling element 252 having atleast a pair of arms 254, 256 which releasably grip a complimentarycoupling element 258. The complimentary coupling element 258 is fixed toa pull wire or cable 260 extending within the delivery catheter 242. Thewire or cable 260 is pulled as shown in FIG. 25B to compress the coilsprings 236 and reduce the distance between each adjacent pair ofmagnets 232, thereby reducing the circumferential length of the annulus40 (FIG. 24C) as the magnets 234 within the LV 14 passively follow themagnets 232 in the CS 46. At this point, the delivery catheter 242 maybe pushed to the left as viewed in FIGS. 25B and 25C causing a crimpingaction of a tube 262 affixed to the most proximal magnet 232. A crimpedportion 262 a is then retained within a recessed portion of the couplingelement 252. At the same time, the gripping arms 254, 256 release thecomplimentary coupling element 258 of the pull wire or cable 260 and thedelivery catheter 242 and pull wire or cable 260 may then be removedleaving the locked fastener system 230 in place as shown in FIG. 25D.

FIGS. 26A-26C illustrate a fastener system 270 which operates the sameas that disclosed in FIGS. 24A-24C and 25A-25D, except that an accordionor bellows type section 272 replaces each coil spring 236, andinternally and externally threaded coupling elements 274, 276 replacethe gripping arms 254, 256 and coupling element 258. It will beappreciated that the operation of the system shown in FIGS. 26A-26C isthe same as that described in the previous embodiment, except thatreleasing the coupling element 276 will involve rotating the pull wireor cable 260 to decouple the threaded coupling elements 274, 276. Itwill be appreciated that the recessed portion 252 a of coupling element252 can have an essentially square cross section. The crimped portion262 a of tube 262 will thus engage the recessed portion and plasticallydeform about it to prevent rotation of coupling element 252 with respectto threaded coupling element 276. The coupling element 276 and cable canthus be effectively unthreaded and released.

FIGS. 27A and 27B illustrate another alternative catheter based fastenersystem 280 which is the same as those described with respect to the twoprevious embodiments, except that the coil springs 236 and accordionshaped bellows sections 272 have been replaced by respective telescopingportions 282, 284 which carry the magnets 232 fixed therein. Also, areleasable coupling 286 is formed by a quarter turn bayonet typefastener as opposed to the gripping arms 254, 256 and element 258, orthe threaded connection 274, 276 of the two previous embodiments. In thepresent embodiment, an elastomeric pad 252 b is seated distal to theproximal component of the bayonet connector 286. When the bayonet 286 isengaged in the delivery position, the pad 252 b creates a load on theproximal component which prevents inadvertent release of the system 280.The recessed segment 252 a of the coupling element can have a squarecross section to prevent rotation of the coupling during disengagementof the bayonet, in a manner similar to the previous embodiment. Thetelescoping portions 282, 284 are flexible and also pivot so that theycan conform to the curved shape of the CS 46. When the pull wire orcable 260 is pulled to the right as illustrated in FIGS. 27A and 27B,the telescoping portions 282, 284 can move together such that detents288 move from one recess 290 to an adjacent recess 292 of the respectivetelescoping portions. The assembly is then locked in place as previouslydescribed and the bayonet coupling 286 is released for purposes ofwithdrawing the delivery catheter 242.

FIGS. 28A and 28B are illustrative of another embodiment which is thesame as the system shown in FIGS. 27A and 27B, except that thetelescoping portions 282′, 284′ are fabricated of a flexible,elastomeric polymer material to allow the fastener system 280′ toconform to the curve of the CS 46 (FIG. 24C). This is to be contrastedwith the fastener system 280 shown in FIGS. 27A and 27B, in which thetelescoping elements 284 are fabricated of a relatively more rigidmaterial. In this previous embodiment, flexibility is gained primarilyfrom the length of the detents 290 and 292, which allow angledpositioning of one telescoping element relative to an adjacent one. Inthe current embodiment, additional flexibility of the fastener isachieved with the length of the detents 290 and 292.

FIGS. 29A and 29B illustrate another system 280″ which is similar tothose described in the previous embodiment, except that the telescopingportions 282″, 284″ only have one recess location 290′ for initiallyretaining the relative positions of the telescoping portions 282″, 284″as shown in FIG. 29A. Also, each telescoping portion 282″, 284″ may haveprojections 296 which act as mechanical fasteners for engaging tissuewithin the CS 46 (FIG. 24C). When the telescoping portions 282″, 284″are drawn together, as described above, the smaller diameter sections282″ are retained in the telescoped position by a locking mechanismoperating on the flexible tensile member 238, such as previouslydescribed, thereby maintaining the shortened condition of the fasteningsystem.

FIGS. 30, 31A and 31B illustrate another catheter based system 300 forplacing magnets adjacent the mitral annulus, such as within the LV 14(FIG. 1A). In this system, a delivery catheter 304 receives a pluralityof annular magnets 306. Magnets 306, for example, may have roughenedouter surfaces 306 a for tissue engagement purposes. The catheter 304has an outer diameter which is expandable to frictionally retain themagnets 306 at spaced apart locations. An internal tube 308 may bewithdrawn, to the left as illustrated in FIG. 30, to release the magnets306 from their frictional engagement with the outer surface of thedelivery catheter 304. As one example, the delivery catheter 304 isshown with a manipulator wire 310 for orienting the direction of thedistal tip 312, and also a core wire 314 for facilitating insertion andremoval of the delivery catheter 304. Once the magnets 306 aremagnetically coupled to additional magnets (not shown) across theannulus tissue, for example, the internal tube 308 may be withdrawnthereby releasing the delivery catheter 304 from magnets 306 andfacilitating its removal by, for example, pulling on the core wire 314.The magnets 306 may be coupled together by a thin flexible sheath 316 orother suitable structure.

FIGS. 32A-32C illustrate another catheter based system of fastenerscomprising a series of magnets 320 held for sliding movement alongparallel wires 322, 324. Additional parallel wires 326, 328 are providedas guide wires to guide the assembly during insertion through a catheter(now shown) to a location adjacent the annulus. A suitable mechanism(not shown), is provided for pushing the magnets 320 together alongwires 322, 324 to reduce annulus tissue, for example, with respect toadditional movable magnets (not shown) on the opposite side of thetissue. The series of magnets 320 is locked in the position shown inFIG. 32B, for example. In this embodiment, magnets 320 are coated with asoft polymer 320 a which frictional engages small stop members 322 a,324 a on wires 322, 324 to assist with retaining desired positions ofthe magnets 322, 324.

FIGS. 33, 33A and 33B illustrate another system of fasteners placed viaa delivery catheter 242 and including a coupling mechanism 244 andlocking mechanism 250 as described above in connection with FIGS.25A-25D. This system is similar to that described in FIGS. 26A-26C inthat bellows or crumple zones 330 are provided between magnets 232, asbest illustrated in FIGS. 33A and 33B to accommodate movement ofadjacent magnets 232 together as they slide along the flexible tensilemember 238 while flexible tensile member 238, which is rigidly attachedto the most distal magnet 232, is pulled to the left as viewed in FIG.33. The operation of this embodiment is otherwise the same as thatdescribed in connection with FIGS. 26A-26C.

FIGS. 34A-34I comprise a series of illustrations of a catheter basedsystem for applying a series of fasteners through tissue generally atthe mitral valve annulus and using guidance magnets 102 a′, 102 b′ and100 a′ (as previously described) in the CS 46 and the LV 14. In thisembodiment, a left ventrical catheter 340 has a portion 342 which usesradio frequency (RF) to effectively drill an initial hole through thetissue and then insert a second larger diameter catheter portion 344which is steerable, for example, as shown in FIGS. 34B-34D, to make asecond hole in the annulus tissue 40. It will be appreciated that thevarious catheters disclosed herein may have distal portions which aresteerable in various manners for accurate positioning purposes. In thisembodiment, tip 344 is movable into a desired hook-like position by aguiding cable 344 a which may be pulled to configure tip 344 into thehooked shape as shown. The catheters utilized herein can includeunidirectional or bi-directional steering. A steering mechanism may bepositioned within and/or on the devices. Typically, the steeringmechanism may include a pull wire 344 a terminating at a flat spring orcollar. The steering system has a more flexible distal section comparedto the proximal catheter tube body. When tension is placed on the pullwire 344 a, the catheter distal end 344 is deflected into a curve, whichhelps direct the device within a heart chamber, for example. The pullwire 344 a may be wound, crimped, spot welded or soldered to the flatspring or collar (not shown) placed in the catheter end 344. Thisprovides a stable point within the device for the pull wire 344 a toexert tensile force and thus steer the device. The more proximal portionof the catheter may be reinforced by incorporating a helically wound orbraided wire therein to provide column support from which to betterdeflect the distal section 344. Alternatively, the steering mechanismmay consist of a superelastic material having a desiredthree-dimensional geometric shape at its distal end and sufficientrigidity to impart this shape in the device. By retracting the preformedsteering wire into the stiffer proximal section of the device, thedistal end of the device straightens. Extending the preformed steeringwire into the more flexible distal section of the device causes thedistal section to assume the shape of the steering wire. Alternatively,a device with a curved section can incorporate a tube or rod that can beadvanced through that section to straighten it. An additional featurethat may be incorporated in the device is a preformed shape in thedistal section of the device. The distal section may be preformed into acurve that biases the device to maximize tissue contact when the deviceis positioned into the appropriate heart chamber. This curve may consistof a single arc or a nonlinear geometry, such as an “S”. A pre-shapedrod, hypotube, wire or coil, created from a memory elastic material suchas nickel titanium or spring steel may be thermally formed into thedesired geometry, and inserted into the distal section (including aseparate lumen) of the device during manufacturing or advanced through adedicated lumen while the device is positioned in the heart. The shapedwire may be attached to the distal tip of the device for thosenon-removable pre-shaped rods and secured to the handle of the device atits proximal end to provide a reinforcing structure throughout theentire length of the device. The device body may also or alternativelybe thermally formed into a desired geometry.

As shown in FIG. 34A, the various systems of this invention may alsoinclude different manners of ensuring that the catheter device(s) is/areproperly position adjacent to tissue prior to use. For example, animpedance measurement device 343 may be coupled to the perforatingelement itself, such as RF wire 342, or electrodes on the perforatingelement or on any separate element carried by the system. Such proximitydetermining devices may be used to confirm contact between the catheterdevice and the tissue surface by comparing the impedance between theelectrode (such as RF wire 342) and a return path (indifferent patchelectrode or second element electrode). When the electrode(s) onlycontact blood, the impedance is substantially higher than when theelectrode element is in contact with the tissue surface. Each electrodeis connected to a signal wire, with the signal wire connected toimpedance measurement device 343. The signal wire may be connected tothe impedance measurement device 343 by way of a connector and cablesystem. The measurement device 343 may be a power supply, a simpleelectrical resistance meter, or any other suitable device and method ofuse.

As further illustrated in FIG. 34C, a balloon portion 346 of the leftventricle catheter 340 may be inflated to stabilize the catheter 340against the tissue 40 as the holes are being formed. As shown in FIGS.34E and 34F, a fastener 348 is delivered through the lumen of thesteerable catheter portion 344 and is coupled with a flexible tensilemember 350 and another fastener 352. The first and second fasteners 348,352 are deployed on the same side of the tissue 40 at spaced apartlocations with the flexible tensile member 350 coupled therebetween.These fasteners 348, 352 may be formed essentially as torsion springmembers which may have a portion which captures and locks against theflexible tensile member 350 in the deployed position as shown in FIG.34F. Once the first fastener 348 is deployed as shown in FIG. 34G, theflexible tensile member 350 may be pulled to plicate the tissue 40between the first fastener 348 and the steerable catheter portion 344.At this time, the second fastener 352 is delivered and captures andlocks with the flexible tensile member 350 to lock the length of theflexible tensile member 350 between the two fasteners 348, 350 with thetissue plicated as shown in FIG. 3411. This process may be repeated, asnecessary, to plicate additional annulus tissue 40 for further annulusreduction.

FIGS. 35A-35F illustrate another catheter device 360 for deliveringmultiple fasteners 362 attached with a flexible tensile member 364, forexample, in the LV 14 at the annulus 40. As best shown in FIG. 35B, thecatheter device 360 includes three fastener delivery portions 366, 368,370. One portion 368 is a central portion at the distal end of thecatheter device 360 and deploys a first fastener 362. Two additionalfastener delivery portions 366, 370 are spaced on opposite sides of thecentral portion 368 and preferably may be actively moved to preferredpositions relative to central portion 368 to deliver additionalfasteners 362. A flexible tensile member 364 couples each fastener 362together as well as to a plurality of pledgets or tissue support members372. A fastener drive mechanism 374 is used to drive one or more of thefasteners 362 through the tissue and comprises a reciprocating rod 376which is activated by spring force developed in a coil spring 378. Whena pair of magnets 380, 382 are decoupled by pulling a wire or cable 384,for example, the spring forces the reciprocating rod 376 upwardly asviewed in FIG. 35B to drive the fastener 362 through the tissue 40. Itwill be appreciated that similar mechanisms may be used with flexibledrive rods 386, 388 in driving the outer fasteners 362 through thetissue, or this same mechanism 374 may be coupled with flexible driverods 386, 388 to simultaneously drive each of the fasteners 362 throughthe tissue 40. All three fasteners 362 are thereby′ deployed, inaddition to the pledgets 372, as illustrated in FIG. 35E. Then, thedrawstring or flexible tensile member 364 are pulled tight to plicatethe tissue 40 as shown in FIG. 35F and a crimp member 390 is applied tolock the flexible tensile member 364 in the tensioned position to retainthe plicated tissue 40 in the desired state.

FIG. 36 illustrates an alternative embodiment of the catheter device 360shown in FIG. 35A-35F, in which the distal end of the catheter device360′ includes a magnet 400 for locking up temporarily with one or moremagnets (not shown) in the CS 46 (FIG. 1A) as previously described. Thisallows the catheter device 360′ to be accurately positioned andtemporarily locked in place proximate the annulus 40 while the anchorsor fasteners 362 are being delivered, cinched and locked in place aspreviously described with respect to FIGS. 35A-35F.

FIGS. 37A-37C illustrate another alternative catheter delivery device orsystem 410, and valve support/fastener system 412 for plicating annulustissue 40 and pulling a posterior leaflet 24 toward an anterior leaflet22. In this embodiment, a C-shaped support member 414 is initiallyretained within a catheter 416 in a nonactivated, compact state as shownin FIG. 37A. When the support member 414 is pushed from the distal endof the catheter 416, it springs into a deployed or activated state asshown in FIGS. 37B and 37C. The anchors or fasteners 418 are retained onthe rod shaped support member 414 for sliding movement and are coupledtogether by one or more flexible tensile members 420. An additionalflexible tensile member 422 extends from another catheter portion 424and provides for secondary cinching or drawstring action. A magnet 426is rigidly coupled to a central fastener or anchor 418 at P2, as shown,or otherwise coupled to the support rod 414 and temporarily locks upwith a magnet 428 in the CS 46 generally as previously described.Fasteners or anchors 418 are then connected to the annulus tissue 40such as by using additional fastening elements (not shown) which aredelivered via another catheter (not shown) within the LV 14, in one ofthe manner previously described. Once the anchors or fasteners 418 aresecured to the tissue 40, the flexible tensile members 420 are pulledthereby pulling each of the fasteners or anchors 418 toward one anotheralong the support member 414. A final or secondary pulling action may beobtained by pulling the flexible tensile member ends 422 extending intothe catheter portion 424 extending from the main catheter 416. Variousmanners may be used to retain the flexible tensile members 420, 422 andanchors 418 at the new positions shown in FIG. 37C, such as by usingcrimp members (not shown), or integrated ratchet-type or frictionalengagement structure (not shown) which automatically locks the flexibletensile members 420, 422 in place as they are pulled.

FIGS. 38A-38I illustrate another catheter based system and method fordelivering, for example, three fasteners or anchors coupled torespective flexible tensile members and cinched together to reduce amitral valve annulus 40. In this embodiment, as shown in FIG. 38A, a CScatheter 430 and LV catheter 432 may temporarily lock up throughmagnetic coupling and an initial hole may be formed through the annulustissue 40 using RF energy applied via a wire 434. A first fastener oranchor 436 coupled with a flexible tensile member 438 may be deployedthrough the hole using a catheter 440 threaded over a guide tube 442.The catheter 440 may be removed and another catheter 444 havingbifurcated portions 444 a, 444 b may be used by threading one of thebifurcated portions 444 a over the flexible tensile member 438.Alternatively, once the first fastener 436 and flexible tensile member438 are deployed as shown in FIG. 38F, the second portion 444 b of thecatheter 440 may be activated and moved to a spaced apart location toform a hole using an RF wire 434 and then deploy a second fastener 446and flexible tensile member 448 (FIG. 38H). Then, the first catheterportion 444 a and second catheter portion 444 b are removed and thefirst catheter portion 444 a is threaded along the second flexibletensile member 448. A third anchor 450 and attached flexible tensilemember 452 are then deployed from the second catheter portion 444 bresulting in three deployed anchors 436, 446, 450 and flexible tensilemembers 438, 448, 452 as shown in FIG. 38H. A crimping and cuttingdevice 460 is then used to pull the flexible tensile members 438, 448,452 and fasteners or anchors 436, 446, 450 together to thereby pull theposterior leaflet 24 toward the anterior leaflet 22 and then a crimpmember 462 is applied to the flexible tensile members 438, 448, 452 andcut to result in the system being fastened generally as shown in FIG.38I. As alternatives to RF energy, other manners and devices may be usedfor forming a hole through tissue prior to or while inserting an anchoror fastener. For example, these may include needles, blades, coringdevices, etc. which can effectively create a starter hole in the tissuesuch that less force is required to drive an anchor into or through thetissue.

As shown in FIGS. 39A and 39B, the crimping and cutting device 460includes a crimping portion 470 comprising jaws 472 a, 472 b withprojections 472 for applying force to the crimp member 462 and a cuttingportion 474 coupled with an RF energy source 476. After the crimpingportion 470 is actuated to crimp the crimp member 462 onto the flexibletensile members 438, 448, 452, the RF energy source 476 is activated tocut the flexible tensile members 438, 448, 452 as shown in FIG. 39Busing cutting element a 477. To facilitate crimping, one threadedportion 478 of the device is rotated with respect to another portion479. This pulls jaws 472 a, 472 b proximally to bring them togetheragainst the crimp member 462.

FIG. 40 illustrates the use of an additional magnet 480 in the leftatrium 12 for supplying additional magnetic force at the junction of theannulus 40 and CS 46. An arrangement of magnets 480, 482, 484 may beused for temporarily locking up the catheter system at the location thatit is desired to deliver a fastener or anchor (not shown), such as inthose manners previously described. FIGS. 40B-40D illustrate analternative fastener delivery system and method for delivering fasteners486 in the left atrium 12 as opposed to the left ventricle 14 aspreviously described. This system is otherwise similar in that magneticguidance and lock up first temporarily occurs between the variousmagnets 480, 482, 484 in the system. Once this magnetic lock up hastaken place, a fastener 486 and flexible tensile member 488 may bedelivered through a steerable portion 490 a of a catheter 490 in theleft atrium 12 such that the fastener 486 is delivered into the leftventricle 14. Steering mechanisms, such as those described elsewhereherein may be used to accurately direct catheter portion 490 a. A numberof fasteners 486 and attached flexible tensile member or members 488 maybe deployed as shown in FIG. 40D and then cinched or drawn togetherusing a crimping and cutting device 460 as previously described. FIGS.41A-41C illustrate another embodiment of a catheter delivered fasteningsystem. In this embodiment, it will be understood that a series offasteners 500, 502, 504 and attached flexible tensile members 506, 508,510 may be delivered as previously described and as shown in FIGS. 41Aand 41B. A delivery catheter 520 may include a balloon 522 forstabilizing against the tissue 40 and/or for positioning respective arms520 a, 520 b, 520 c of the catheter device 520 while delivering theanchors or fasteners 500, 502, 504 and each of their attached flexibletensile members 506, 508, 510. A valve support member 530 may then bedelivered through a catheter (not shown) as shown in FIG. 41B. Thesupport member 530 has eyelets 532, 534, 536 which are threaded overeach of the respective flexible tensile members 506, 508, 510.Respective crimps 538, 540 are applied to the outer eyelets 532, 536 andthe flexible tensile members 506, 510 cut proximate to each crimp member538, 540. The central flexible tensile member 508 is pulled to therebypull the posterior leaflet 24 at P2 toward the anterior leaflet 22. Whensuitable tension and pulling action has taken place, a third crimpmember 542 is applied proximate the central eyelet 534 at the apex ofthe V-shaped and the flexible tensile member 508 is cut proximate to thecrimp member 542. This results in approximation of the posterior andanterior leaflets 22, 24 as shown in FIG. 41C.

FIGS. 42A and 42B illustrate one possible anchor or fastener 550 usablewith the various systems of the present invention. Such an anchor 550may be rigidly coupled to a flexible tensile member 552, or coupled suchthat the anchor or fastener 550 slides along the flexible tensile member552, as necessitated by the fastening system in which the fastener 550is being used.

FIG. 43 is a side elevational view of an alternative fastener 560 whichis similar to that shown in FIGS. 42A and 42B, except that the fastener560 has a curved outer profile. The convex surface 562 of the curvedouter profile is adapted to engage tissue and cause less trauma to thetissue than the flat profile shown in FIGS. 42A and 42B.

FIGS. 44A-44C illustrate another alternative fastener 570 useful in thevarious systems and methods of this invention. This fastener 570includes two radially expandable portions 572, 574 which may bedelivered through a catheter 576 in their nonexpanded state shown inFIG. 44A, and then expanded on opposite sides of the tissue 40 to betrapped therebetween, as shown in FIGS. 44B and 44C.

While the present invention has been illustrated by a description ofvarious preferred embodiments and while these embodiments has beendescribed in some detail, it is not the intention of the Applicant torestrict or in any way limit the scope of the appended claims to suchdetail. Additional advantages and modifications will readily appear tothose skilled in the art. The various features of the invention may beused alone or in any combination depending on the needs and preferencesof the user. This has been a description of the present invention, alongwith the preferred methods of practicing the present invention ascurrently known.

What is claimed is:
 1. A method of applying a fastener to an annulus ofa heart valve, comprising: placing a first magnet in a coronary sinususing a first catheter, placing a second magnet adjacent the annulus,outside of the coronary sinus, using a second catheter, magneticallycoupling the first and second magnets, and applying a fastener into theannulus while the first and second magnets are coupled.
 2. The method ofclaim 1, wherein a single catheter device is used to apply the fastenerand place the second magnet adjacent the annulus.
 3. A system formodifying an annulus of a heart valve to reduce regurgitation of bloodthrough the valve, comprising: a first catheter, a first magnet coupledwith said first catheter in such a manner that said first catheter isoperative to deliver said first magnet adjacent to the annulus, a secondcatheter, a second magnet coupled with said second catheter in such amanner that said second catheter is operative to deliver said secondmagnet adjacent to the annulus, and a fastener delivery device coupledto at least one of said first and second catheters and configured tosecure a first fastener to the annulus.
 4. The system of claim 3,wherein said fastener delivery device comprises a steerable catheterportion so as to enable delivery of a fastener to a desired position. 5.The system of claim 4, wherein said fastener delivery device is coupledat predetermined angle relative to an axis of magnetic attractionbetween said first and second magnets.
 6. The system of claim 3, furthercomprising a plurality of fastener delivery devices coupled to at leastone of said first and second catheters and configured to deliverrespective fasteners at spaced apart locations along the annulus.
 7. Thesystem of claim 6, further comprising the plurality of fasteners coupledtogether with at least one flexible tensile member such that saidflexible tensile member is capable of drawing the fasteners together andthereby reducing the circumferential length of the annulus.
 8. Thesystem of claim 3, wherein said fastener delivery device furthercomprises a catheter portion, and further comprising: an RF poweredelement extendable from within said catheter portion and operable toform an aperture in the annulus for insertion of the fastener.
 9. Thesystem of claim 3, wherein at least one of said first and secondcatheters is coupled with an inflatable member configured to stabilizesaid fastener delivery device adjacent the annulus.
 10. The system ofclaim 3, wherein said fastener delivery device is a catheter portion,and further comprising: said first fastener coupled with a flexibletensile member and received within said catheter portion, said firstfastener and flexible tensile member deployable through said catheterportion.
 11. The system of claim 10, wherein said first fastener furthercomprises a torsion spring member configured to expand after deploymentfrom said catheter portion.
 12. The system of claim 11, wherein saidtorsion spring member locks against said flexible tensile member upondeployment from said catheter portion.
 13. The system of claim 10,further comprising: a second fastener coupled with said flexible tensilemember, at least one of said first and second fasteners movable alongand then lockable to said flexible tensile member thereby allowing adistance between said first and second fasteners to be shortened andlocked resulting in a shortening of the circumferential length of theannulus.
 14. A catheter adapted to be a guide element placed within avessel, comprising: a distal support portion, and first and secondmagnets carried on said distal support portion, said first and secondmagnets positioned in spaced apart relation such that a gap is formedbetween said first and second magnets and repelling poles face eachother, whereby a circumferential virtual magnetic pole emanates aroundthe gap between said first and second magnets.